1. Field of the Invention
This invention relates to filtering of liquids, and, more particularly, to a vibrating sieve filter and a method of cleaning in place or purging the undesirable materials.
2. Description of the Prior Art
Liquids used in industrial processes often require selective filtering to eliminate only the undesirable contaminate particles. Typically, this is accomplished with a bag type semi-permanent or disposable filter in which the liquid being filtered is passed through a bag in a basket support. Alternatively, disposable cartridge filters of various configurations are used. The surfaces of these types of filters become quickly clogged with materials including those the removal of which is not desired.
Improved performance in filtration has been accomplished in many instances by the adaption of sieving techniques. A cylindrical perforated steel basket with a screen covering replaces the cloth or paper composition bag. The cylindrical screen is placed in a cylindrical casing or housing and the liquid to be filtered is generally admitted at the bottom of the housing for flow through the screen to the interior of the screen cylinder and upwardly to a top outlet. In some instances a space is left between the bottom of the screen cylinder and a housing to provide a vibrator which induces vibration into the incoming liquid helping to keep the smaller particles in suspension for improved sieving.
This invention is directed to an improved type of sieving filter and to improved techniques for using vibration.
When a bag type or sieving type filter becomes clogged, in-place cleaning is typically accomplished by backwashing which involves piping a cleaning fluid through the normal filter outlet for discharge through the normal filter inlet. Piping for this type of purge is cumbersome, and down time for purge is often excessive, requiring multiple filters in parallel to allow sequential backwash purging.
It is to an improved cleaning-in-place system to which this invention is also directed.
When the filter becomes clogged to such an extent that in-place cleaning is ineffectual, disassembly of piping is sometimes necessary to remove the filter for cleaning or replacement.
It is to an improved arrangement for sieving cylinder removal or cleaning without disconnecting piping to which the present invention is also directed.